Yarn splicing apparatus

ABSTRACT

An improved yarn splicing apparatus having particular utility in the joining together of undrawn multifilament yarn ends is described which comprises a pair of spaced-yarn clamps, means for drawing and relaxing a yarn segment intermediate said clamps, an air entangling jet for entangling the filaments of the yarns, and means for operating the aforesaid elements in sequence, whereby the two yarn ends are clamped then, drawn to a predetermined ratio and relaxed prior to air entanglement of the filaments.

United States Patent 1191 Cardell July 9, 1974 [54] YARN SPLICING APPARATUS 3,527,025 3/1971 lrwin 57/22 V 3, 1,486 6197] D'b l .t 7 22 75 Inventor: Max L. Cardell, Shelby, NC. 58 b e 5 [73] Assignee: Fiber Industries, Inc., Charlotte, FOREIGN PATENTS OR APPLICATIONS N C 956,992 4/1964 Great Britain 57/22 [22] Filed: 1973 Primary Examiner-Donald E. Watkins [21] Appl. No.: 411,581 i 57 ABSTRACT [52] US. (i1. 511/5159 An improved yam Splicing apparatus having particular C 2 utility in the j g together of undrawn multifilament [58] held 0 Search 34 22 yarn ends is described which comprises a pair' of 5 spaced-yarn clamps, means for drawing and relaxing a 1 yarn segment intermediate said clamps, an air entan- [56] References cued gling jet for entangling the filaments of the yarns, and

, UNITED STATES PATENTS means for operating the aforesaid elements in se- 3,345,809 10/1967 Gemeinhardt et al. 57/22 quence, whereby the two yarn ends are clamped then, 3,407,583 10/ 1968 lrwin et al 57/22 drawn to a predetermined ratio and relaxed prior to 3,477,217 11/1969 Bell et al air entanglement f the filamen|[s 3,487,618 l/l970 Arguelles..... 3,525,207 8/1970 Irwin 19 Claims, 12 Drawing Figures m B| D A I66 I64 I62 2|2 76 1a 9 56 68 no 9 as we 90 L 6 9 as m 8 e0 88 46 H I IBO r we 2 If 9 OC I m [23 I 210 A 76 202 p 2 74 '46 ,t 200 I 108 D l I I L A I58 B 128 I52 I30 I36 I32 1 YARN SPLICING APPARATUS being used herein to include yarns of staple fibers, it is frequently necessary to join two yarn ends together as aresult of yarn breakage or the need to join the trailing end of the yarn on one bobbin with the leading end of the yarn on another bobbin. While the two yarn ends .may, of course, be joined by simply tieing the two ends into a knot, this procedure is undesirable since the knot thus formed will frequently snag in subsequent processing resulting in further breakage. Furthermore, the knot detracts from the appearance of the ultimate arti' cle formed from the yarn.

To overcome these difficulties, multifilament yarn ends are frequently jointed together by air entanglement. In this method, two yam ends are clamped in parallel alignment at two spaced points and the yarn segments between the two spaced points are subjected to a jet of fluid, usually air, which produces a turbulent zone in which the filaments of one yarn segment are entangled with the filaments of the other yarn segment resulting in joining of the two yarn ends.

While joining of yarn ends by previous air entanglement methods produces yarn joints which are less likely to snag in subsequent processing and which are less noticeable, the yarn joints formed tend to be somewhat weaker, and are especially so when the yarns being joined together are undrawn yarns, the terms being used herein to include partially drawn yarns, wherein the yarn joints frequently separate in subsequent drawing operations. Also, these joints tend to vary in uniformity since many of the steps involved in forming the joint are manual in nature.

While the prior art, as exemplified by US. Pat. Nos. 3,345,809 and 3,477,217, has described many devices for use in the joining together of yarn ends by air entanglement in a somewhat automatic manner, there has heretofore been no apparatus which would automatically and consistently join the ends of undrawn yarn with uniform joints having sufficient strength to withstand subsequent drawing to a commercially practicable extent.

SUMMARY OF THE INVENTION The yarn splicing apparatus of the present invention may be of either a hand held or a stationary construction. In either event, the apparatus comprises a pair of spaced yarn clamps, a means for drawing to a predetermined extent andthen relaxing a segment of yarn held between the yarn clamps, and means for directing an air jet against the yarn segments to effect air entanglement. Additionally, the present apparatus comprises a means for operating the aforesaid elements in sequence so that the two yarn segments are clamped, then drawn to a predetermined ratio and relaxed, and thereafter air entangled. The apparatus may additionally include means for automatically closing a cover over the air entanglement chamber prior to air entanglement.

In the preferred embodiment described hereinafter, this sequence regulating means is comprised of a plurality of sequentially operated valves which, upon being opened, introduce compressed air to the respective elements. It will be apparent, however, that other operating means such as timing cams (shown in the altemative embodiment), or limit switches may be employed for this purpose.

In the accompanying drawings:

FIG. 1 is a side elevation of the preferred embodiment with a major portion of the housing removed.

FIG. 2 is a cross-sectional view along line A-A of I FIG. 1 illustrating the pair of spaced clamps forming a part of the apparatus.

FIG. 3 is a cross-sectional view along line B-B of FIG. 1 illustrating the operating mechanism for the draw-relax assembly.

FIG. 4 is a cross-sectional view along line C-'C of FIG. 1 illustrating another section of the operating mechanism for the draw-relax assembly.

FIG. 5-7 are cross-sectional views along line D-D of FIG. 1 illustrating the draw-relax assembly of the preferred embodiment at various stages of operations.

FIG. 8 is a plan view of the alternative embodiment illustrating the clamping, draw-relax, and air entanglement assemblies.

FIG. 9 is a plan view of the means utilized in the alternative embodiment for achieving sequential operation of the clamping, draw-relax, and air entanglement assemblies.

El.Q-. .9- -a .sest shalsids View of e a t l ment assembly taken along line A-A of FIG. 8. v

FIG. 11 is a sectional side view of one of the yarn clamps of the alternative embodiment.

FIG. 12 is a schematic of the alternative embodiment particularly illustrating the arrangement of the fluid lines.

DESCRIPTION OF THE PREFERRED EMBODIMENT The preferred embodiment of the preferred invention as illustrated in FIGS. 1-7, is a handheld apparatus comprised of a pistol-shaped housing 10 preferably of a molded material which, when positioned as shown in FIG. 1, is comprised of a generally horizontal operating head and a downwardly inclined butt. Housing 10 either encloses or has connected thereto a clamping assembly, a draw-relax assembly, an air entangling assembly, and an actuation assembly for operating the other assemblies in sequence. For convenience of description, these assemblies will be described under separate headings with their inter-relationship being discussed in greatest detail as part of the discussion of the operation of the preferred embodiment.

Clamping Assembly The clamping assembly, generally 12, is located at the terminal end of the operating head of the apparatus and serves to secure two yarn ends in parallel alignment at two spaced points so that the yarn segments between the two points may be drawn to a predetermined draw ratio, relaxed, and then subjected to air turbulence to join the ends of entanglement of the filaments comprising the yarn ends. Clamping assembly 12 is comprised of a pair of clamping heads 14 and 16 which form, along with housing 10, the walls of a clamping air chamber 18 between and communicating with clamping heads 14 and 16. The outer surfaces 20 and 22 of clamping head 14 and 16 are faced with resilient facing discs 24 and 26 which are preferably formed of a mate rial such as neoprene, the discs 24 and 26 serving to prevent abrasion of yarn being held within clamping assembly 12 and insure that the ends are firmly clamped; A pair of yarn guides 28 and 30 are spaced outwardly from clamping heads 14 and 16 to form a pair of yarn receiving channels 32 and 34 between guides 28 and and heads 14 and 16, respectively, and aid in the placement of the yarn ends within the channels. Also extending from the outer faces 20 and 22 of heads 14 and 16 are a pair of plungers 36 and 38, respectively, which act against springs 40 and 42 mounted within housing 10 to urge clamping heads 14 and 16 inwardly into clamping air chamber 18. Air Entangling Assembly The air entangling assembly, generally 44, utilized to entangle the filaments of the yarn ends is comprised of a transversely positioned block 46, having in its upper surface an elongated trough 48 into which the yarn ends are placed for entanglement. The underside of block 46 contains an air inlet channel 50 which communicates with branched air channels 52 and 54 which extend to air nozzles 56 and 58, respectively. Air nozzles 56 and 58 exhaust through sidewalls 60 and 62 respectively, into trough 48 and are in an opposed relationship so that turbulence is created within trough 48 during operation of the assembly. Trough 48 is covered during operation by cover 64 which is positioned at one end of a lever arm 66. Lever arm 60 is caused to pivot on dowel pin 68 to raise and lower cover 64 into and out of engagement with block 46 by plunger connected to lever arm 66 on the opposite side of dowel pin 68 from cover 64 by dowel pin 72. Plunger 70 in turn extends downwardly into a cover air chamber 74 and is urged downwardly by spring 76. Draw-Relax Assembly The draw-relax assembly used to draw the yarn segments between clamps 14 and 16 to a predetermined draw ratio and then relax the yarn segments prior to air entanglement, generally 78, is comprised of a pair of parallel longitudinally extending, rotatable rods and 82. The ends of rods 80 and 82 extending in the directionof air assembly block 46 are joined to yarn drawing arms 84 and 86, respectively. Arm 84 is comprised of a first segment 88 which adjoins rod 80 and is coaxial therewith, a second segment 90 which joins segment 88 andextends upwardly therefrom at an angle of about thirty degrees from the horizontal, a third segment 92 which adjoins segment 90 and extends horizontally therefrom, and a fourth segment 94 which adjoins segment 92 and extends upwardly and rearwardly therefrom at an angle of 30 with segment 92. Rod 82, hidden in the drawings by rod 80 and housing 10 is identically constructed. Rod 80 is freely rotatable within bushings 96 and 98. Rod 82 is similarily supported. A torsion spring 100 connects rod 80 to housing 10 to re sist rotation of rod 80 from its initial position as shown in FIG. 4. Extending downwardly from between rods 80 and 82 is an actuator rod 102 which is connected operably with rods 80 and 82 by way of a pull cord 104 having its ends wrapped about rods 80 and 82 and its center portion extending downwardly around pin 106 on actuator rod 102. Actuator rod 102 has affixed within its lower end an adjustable pin 108 for controlling the time at which the draw relax assembly is actuated during the operational sequence.

It will be apparent to the skilled artisan upon reading the present disclosure that variation of the length and angularity of the rod segments will vary the draw ratio.

Actuation Assembly Actuation of the aforesaid clamping, air entangling and draw-relax assemblies in sequence is achieved with an actuation assembly including a trigger 110 which extends downwardly from housing 10 through opening 112 therein. The upper end of trigger 110 is integral with a pivot arm 114 which is pivoted about dowel pin 116 extending through the end opposite trigger 110. A trigger return spring 117 connected to housing 10 urges trigger 110 to the open position.

Within the butt portion of housing 10 are located three 2-way valves 118, 120 and 122 which communicate with main air chamber 124, chamber 124 being supplied with compressed air through air hose 126 from an appropriate source. Valves 118, 120 and 122 are opened by the action of plungers 128, 130 and 132, respectively, which have contacting heads 134, 136 and 138 at their lower ends slidable within cylinders 140, 142 and 144, respectively. The ends of plungers 128, 130 and 132 opposite valve contacting heads 134, 136 and 138 are pivoted on a generally horizontal swing bar 146 by the use of dowel pins 148, 150 and 152, respectively. Swing bar 146 in turn is pivoted about dowel pin 154 which is secured within housing 10. The end of swing bar 146 opposite dowel pin 154 is connected to an upwardly extending pawl 156 with a dowel pin 158.

In order to maintain valves 118, 120 and 122 in an open position for a predetermined period of time, and thus control the desired degree of entanglement of the filaments of the yarn segments, a timing mechanism is provided as part of the apparatus to control the closing of the valves independently of the movement of trigger 110 to the open or initial position.

More specifically, this timing mechanism is comprised of a timing piston 160 comprised of a main body 162 and a spring 164 moveable within cylinder 166. A fluid reservoir 168 containing a fluid, e.g., air, maintained under pressure by spring 170, communicates with cylinder 166 through inlet conduit 172 and exhaust conduit 174 in housing 10. A check valve 176 prevents return of fluid through conduit 172, while the rate of return of fluid through exhause conduit 174 is controlled by adjustable needle valve 180 positioned therein.

Timing piston 160 is operatively connected to valve plungers 128, 130 and 132 by arm 182 extending outwardly from body 162 and connected to a bell crank 184 opposite arm 182 with pin and extends outwardly therefrom. Link 188 has a slot 192 in the face thereof in which rides a pin 194 secured to the end of pawl 156 opposite swing bar 146. Pawl 156 is comprised of a shoulder portion 196 intermediate pins 158 and 194 to operatively connect trigger 110 thereto by way of a pin 198 extending outwardly from pivot arm 114 to releasably engage shoulder 196 of pawl 156.

In order to release the trigger from the timing mechanism, a drive pawl 200 having a bell crank contacting face 202 and a release shoulder 204 is pivoted on pivot arm with dowel pin 206. Face 202 is urged toward bell crank 184 by a spring 208. An adjustable release screw 210 is positioned within housing 10 to contact shoulder 204 upon downward movement of pivot arm 114. Bell crank 184 is urged toward timing piston 160 by an extendible return spring 212 secured between the upper end of bell crank 184 and housing 10.

Operation of the Preferred Embodiment valve 118 permitting compressed air to enter clamping air chamber 18 through conduit 119. As a result,

clamping plungers 36 and 38 are moved outwardly against yarn guides 28 and 30 to secure the yarn ends between resilient facing discs 24 and 26 and yarn guides 28 and 30, respectively.

After clamping of the yarn ends is achieved, further movement of trigger 110 produces a downward movement. of actuator rod 102 by the contacting of pin 108 against trigger 110 resulting in a movement of arms 84 and 86 outwardly to the position shown in FIG. 6 to draw the yarn segments and then downwardly as shown in FIG. 7 to relax the drawn yarn segments. Thus as arms 84 and 86 move to the position shown in FIG. 5, the yarn segment between the two clamped points is drawn to a predetermined extent, e.g., from 2:1 to 6:1,

normally 3:1 to 5:1, depending upon the angularities of the segments of the arms 84 and 86 and then relaxed by further movement of arms 84 and 86 to the positions shown in FIG. 6. Also, movement of arms 84 and '86 from the position illustrated in FIG. 6 to the position shown in FIG. 7 lowers the two yarn segments into trough 48 in block 46.

Thereafter, valve 120 is opened by movement of plunger 130 permitting compressed air to flow from chamber 124 through conduit 121 to trap air chamber 74' raising plunger 70 within chamber 74 to pivot lever arm 66 about dowel pin 68 and lower cover 64 into contact with block 46 to prepare the air entanglement assembly for operation.

Finally, plunger 132 is brought into, contact with valve 122 to permit air to flow from chamber 124 through conduit 123 to trough 48 through nozzles 56 and 58, thus creating turbulence within trough 48 to cause entanglement of the filaments of the two yarn segments.

- As trigger 110 is pressed toward housing 10, timing piston 160 is withdrawn from cylinder 166, causing fluid to enter cylinder 166 through inlet conduit 172 as a result of the vacuum created and the pressure of spring 170.

When trigger 110 reaches its fully compressed position, shoulder 204 on drive pawl 200 contacts screw 210, releasing face 202 from engagement with bell crank 184, thus permitting bell crank 184 to pivot about pin 116 under the action of return spring 212. Piston 160 then moves into cylinder 166 under the action of return spring 212 forcing fluid back into reservoir 168 through exhaust conduit 174, the rate of return of piston 160 being controlled byneedle valve 180 for a predetermined period, e.g., 0.5 to 10 seconds, preferably about 1.5 seconds, to insure adequate entanglement of the yarn filaments and uniformity of joints from operation to operation.

Rearward movement of bell crank 184 also withdraws shoulder 196 on pawl 156 from contact with pin 198, thus releasing trigger permitting its independent return under the action of trigger return spring 117. Movement of pawl 156 upwardly under the action of bell crank 184 sequentially closes valves 118, and 122 to complete the operation. Upon completion of the operation, the joined yarn ends are removed and any excess yarn is trimmed away.

ALTERNATIVE EMBODIMENT the utilization of these modifications in the hand-held unit of the preferred embodiment, as well as the utilization of the assemblies forming part of the preferred embodiment as part of the alternative embodiment.

The alternative embodiment of the present invention as illustrated in FIGS. 812 ofthe drawings is comprised of a clamping assembly which includes a pair of yarn clamps 214 and 216. Clamp 214 is stationary and is comprised of an upright stationary jaw 218 having a yarn receiving edge 219 and a moveable jaw 220 having a yarn receiving edge 221. Moveable jaw 220 is faced with a resilient disc 222 on the surface adjacent to stationary jaw 218. Jaw 220 is moveable relative to jaw 218 under the action of a plunger 224 hinged to jaw 220 with a pivot pin 226 and extending into clamp air cylinder 228.

Clamp 216 is constructed in the same manner as clamp 214, but is moveabletoward and from clamp 214 under the action of a draw plunger 230 which is connected to clamp 216 and moveable into and out of a draw-relax air cylinder 232 situated along an axis extending between clamps 214 and 216. Specifically, clamp 216 is comprised of a stationary jaw 234 having a yarn receiving face 235, jaw 234 being positioned parallel to jaw 218 on clamp 214, and a moveable jaw 236 carrying a resilient disc 238;. opening and closing of jaws 234 and 236 is effected in the same manner as jaws 218 and 220.

The air entanglement assembly of the alternative embodiment is comprised of a stationary section, generally 240, and a moveable section, generally 242. Stationary section 240 is comprised of a block 246 having a yarn receiving trough 248 situated along a line connecting edges 219 and 256 of jaws 218 and 234. Stationary section 240 further comprises an air nozzle 250 communicating with trough 248 and an air conduit 252 extending from nozzle 250 through block 246 to con- I nect with a suitable source of compressed air.

Moveable section 242 of the air entangling assembly is comprised of a block 254 having a concave base 256 with a trough 258 therein. Block 254 is carried on the end of a cylindrical plunger 260,. and contains an air nozzle 262 extending through block 254 between trough 258 and the interior of plunger 260. Plunger 260 rides within air cylinder 264 and forms with cylinder 264, a cover air chamber 266 and an air jet chamber 268. A compressed air inlet 270 communicates with cover air chamber 266 through cylinder 264, while air inlet 272 communicates with air jet chamber 268 through cylinder 264. Both inlet 270 and 272 are connected to a suitable source of compressed air.

Plunger 260 is urged into cylinder 264 under the action of return spring 274.

. In order to provide sequential operation of the clamping, draw-relax, and air entanglement assemblies, the alternative embodiment is further provided with an actuator means comprised of a plurality of air lines connected through a plurality of 2-way valves to a compressed air source, and a plurality of timing cams for opening and closing the valves in sequence to obtain the sequential operation of the assemblies.

More specifically, the actuator assembly-is comprised of a compressed air cylinder 276 which communicates with the clamping, draw-relax and air entangling assemblies through air lines 278, 280, 282, 284, and 286 extending through 2-way valves 288, 290, 292, 300 and 302, respectively. Air line 278 joins with the air cylinders operating clamps 214 and 216; air line 280 joins with air cylinder 232 to operate plunger 230 and thus moves clamp 216 away from clamp 214; air line 282 joins with inlet 270 to communicate with cover air chamber 266; and air lines 284 and 286 join with conduits 252 in stationary section 240 of the air entangling assembly and inlet 272 of moveable section 242 of the air entangling assembly, respectively, to provide compressed air to nozzles 250 and 262.

. Valves 288, 290, 292, 300, and 302 are controlled respectively by timing cams 304, 306, 308, 310 and 312 which are carried on a shaft 314 extending through a one revolution clutch 316 to a drive motor 318.

I In operation, a pair of yarn ends to be joined are looped over edges 219 and 236 of clamps 214 and 216 and between jaws 218 and 220 of clamp 214 and jaws 234 and 236 of clamp 216. The apparatus is then enegerized by completing an appropriate electrical circuit, not shown, to engage clutch 316 causing one revolution of shaft 314. As shaft 314 begins rotation, timing cam 304 opens valve 288 permitting air to flow from air cylinder 276 through air line 278 to activate clamps 214 and 216. Upon further rotation of shaft 314, valve 290 is opened by cam 306 permitting air to flow from cylinder 276 through air line 280 to draw-relax cylinder 232, thus moving clamp 216 away from clamp 214 to draw the yarn segments held therebetween. Upon further rotation of cam 306, valve 290 is closed, permitting clamp 206 to return toward clamp 214, thus relaxing the yarn segments.

Further rotation of shaft 314 engages cam 308 and with valve 292, permitting air to flow from cylinder 276 to cover air chamber 266 within cylinder 264, moving block 354 toward and against block 246 engaging trough 258 against trough 248 to enclose the air entangling chamber and position the yarn segments within troughs 248 and 258. Further rotation brings cams 310 and 312 into contact with valves 300 and 302, opening air lines 284 and 286 between cylinder 276 and air nozzles 250 and 262 permitting air to be injected into troughs 248 and 258 to entangle the yarn filaments. Further rotation of the shaft to its initial position releases the cams from engagement with the valves, returning the apparatus to its initial position to complete the operation and permit removal of the joined yarn ends.

It will be obvious to one skilled in the art that the present invention is not limited to the two embodiments shown, and that many modifications and variations may be made without departing from the spirit and scope of the present invention. For example, while it is preferred to use compressed air to operate all of the assemblies, the clamping and draw-relax assemblies may be operated through the use of mechanical gearing means. Further, air entanglement assemblies of different construction from that shown may be employed so long as the desired entanglement of the filaments is achieved. Also, sequential operation of the assemblies can be achieved through the use of limit switches, or the like.

What is claimed is:

1. An improved apparatus for uniformly joining two segments of multifilament yarn by fluid entanglement of the filaments thereof comprising a. a clamping assembly comprised of a pair of spaced yarn clamps for securing the two yarn segments in abutting, parallel alignment;

b. a draw-relax assembly for drawing the yarn segments held between said yarn clamps to a predetermined draw ratio and then relaxing said yarn segments;

c. a filament entangling assembly for entangling the filaments of one yarn segment with the filaments of the other yarn segments to form a joint; and

d. an actuator assembly for actuating assemblies (a), (b) and (c) in sequence, whereby said draw-relax assembly is actuated after actuation of said clamping assembly and prior to actuation of said filament entangling assembly.

2. The apparatus of claim 1, wherein the draw-relax assembly is comprised of a means for moving said pair of yarn clamps aparta'predetermined distance to draw the yarn segments to a predetermined draw ratio and then moving said clamps toward each other to relax the yarn segments.

' 3. The apparatus of claim 1, wherein said draw-relax assembly is comprised of a pair of yarn supporting arms positioned intermediate said yarn clamps and means for moving said arms apart a predetermined distance to draw the yarn segments and then move said arms toward each other to relax the yarn segments.

4. The apparatus of claim 1, wherein said clamping, draw-relax and filament entangling assemblies are pneumatically actuated.

5. The apparatus of claim 4, wherein said actuator assembly is comprised of a plurality of air lines connecting said clamping, draw-relax and filament entanglement assemblies with a source of compressed air, a plurality of valves controlling the flow of air through said air lines, and means for sequentially opening said valves.

6. The apparatus of claim 5, wherein said means for sequentially opening said valves is comprised of a plurality of plungers and means for bringing said plungers sequentially into contact with said valves.

7. The apparatus of claim 5, wherein said means for sequentially opening said valves is comprised of a plurality of timing cams.

8. An improved apparatus for uniformly joining two segments of multifilament yarn by air entanglement comprising a. a pneumatically operated clamping assembly comprised of a pair of spaced yarn clamps for securing the two yarn segments in abutting, parallel alignment;

b. a pneumatically operated draw-relax assembly for drawing the yarn segments held between said yarn v 9 clampsto a predetermineddraw ratio and then re I laxing said yam segments;

cxa pneumatically operated filament entangling assembly for entangling the filaments of one yarn segment with the filaments of the otheryamsegments :to form ajoint; and I d; anactuator assembly for actuatingassemblies (a),

(b) and (c)in sequence wherebysaid draw-relax assembly is acttiated after actuation of said clamping assembly and before actuation of saidfilament 'entangling assembly, said actuator assembly comprising a plurality of air conduits connecting said clamping, draw-relaxfand filament 'entangling as-- 'semblies with a source of compressed air, a plurality of valves controlling the flow of air through said conduits, valve opening means for opening said valves in sequence and valve closing means for closing said valves. t 9.,The apparatus of claim 8, wherein said apparatus is a hand-held apparatus having a pistol-shaped housing and said valve opening means comprises a trigger extending from said housing;

relax assembly comprising'apair of parallelshafts carrying angularly extendingyarn'supporting arms having yarn engaging portions and means for rotating one of I l0. The apparatus of claim 8, wherein said valve closi ing means operates independently of said valve opening means. i

, l'l. The apparatus of claim 10, wherein said valve closing means includes a timer mechanism for" closing said valve s apredete'rmined period of time after opening of said valvesby said valve opening means.

12: T heapparatus'of claim 11,- wherein said timer mechanism isadjustable. f

13. An improved apparatus for uniformly joining two segments of undrawnmultifilament yarn byair entanglement of thefilaments thereof comprising a. a yarn clamping assembly including a pair of axially aligned clamping plungers having outwardly extending yarn engaging faces, a pair of yarn guides spaced outwardly from said clamping plungers to form a pair of yarn receiving channels, and a first air chamber between saidplungers, whereby introduction of compressed air into said chamber urges said plungersinto said channels to clamp yam segments between said faces and said yarn guides;

b. a'draw-relax assembly for-drawing and'relaxing I yarn segments extending between said channels; c. an air entangling assembly comprised of a block having an elongated trough therein, an air nozzle communicating with said trough, a cover, and 3 pneumatic means including a second air'chamber for moving said coverinto engagement with said block over said trough; and I d. an actuator assembly comprised of afirst air conduit connectingsaid first air chamber with a source I of compressed air, afirst valve controlling the flow.

, of air through said first conduit, a second air conduit connecting said second air chamber with a source of compressed air, a second valve forcontrolling the flow of air through said second air conduit,a third air conduit connectingsaid air nozzle said shafts clock-wise and the other of said shafts counter-clock-wise to move said yam engaging portions .apart and then together; said trough in said block being supporting arms.

15. The apparatus of claim 13, wherein said control means is a trigger and said assembliesar'e supported on a pistol-shaped housing. I r i I l6. Animprovedapparatus for uniformly joining two segmentsof undrawn multifilamentyarn comprising. a. a pair of spaced first and second pneumatically operated yarn clamps, said second yarn clamp being moveable; I I I I I I ;b. a first'pneumatic cylinder having a first plunger sealigned with said yarn engaging portions of said yarn curedfat its outer end to said second clamp, said cylinder being axially aligned with said clamps, said i I; plung'erbeing moveable away ,fromfsaid first clamp I on introduction of compressed air into said fir cylinder;

-c. an air entangling assembly comprised of astation ary portion including a yarn receiving trough and an air nozzle communicating with said trough and a moveable cover portion; I d. a second pneumatic cylinder having a second plunger secured to said moveable cover portion of said air entangling assembly and being axially aligned with said stationary and moveable portions of said air entangling assembly, said plunger being moveable toward said stationary portion upon introduction of compressed air into said cylinder; and

actuator means for introducing compressed'air in sequence to said clamps, said first cylinder, said second cylinder and said air nozzle. 1 17. The apparatus of clamp l6 wherein said second plunger is positioned along an axis transverse to the axis of said first plunger and extending between said yam clamps. I r

18. The apparatus of claim 16, wherein said actuator means is comprised of air lines connectingsaid clamps, cylinders and air nozzle with a compressed air source, valves controlling-the flow of air through said air lines, and valve opening means for sequentially opening said valves.

. 19. The apparatus of claim 17, wherein said valve openingmeans is comprised of timing cams. 

1. An improved apparatus for uniformly joining two segments of multifilament yarn by fluid entanglement of the filaments thereof comprising a. a clamping assembly comprised of a pair of spaced yarn clamps for securing the two yarn segments in abutting, parallel alignment; b. a draw-relax assembly for drawing the yarn segments held between said yarn clamps to a predetermined draw ratio and then relaxing said yarn segments; c. a filament entangling assembly for entangling the filaments of one yarn segment with the filaments of the other yarn segments to form a joint; and d. an actuator assembly for actuating assemblies (a), (b) and (c) in sequence, whereby said draw-relax assembly is actuated after actuation of said clamping assembly and prior to actuation of said filament entangling assembly.
 2. The apparatus of claim 1, wherein the draw-relax assembly is comprised of a means for moving said pair of yarn clamps apart a predetermined distance to draw the yarn segments to a predetermined draw ratio and then moving said clamps toward each other to relax the yarn segments.
 3. The apparatus of claim 1, wherein said draw-relax assembly is comprised of a pair of yarn supporting arms positioned intermediate said yarn clamps and means for moving said arms apart a predetermined distance to draw the yarn segments and then move said arms toward each other to relax the yarn segments.
 4. The apparatus of claim 1, wherein said clamping, draw-relax and filament entangling assemblies are pneumatically actuated.
 5. The apparatus of claim 4, wherein said actuator assembly is comprised of a plurality of air lines connecting said clamping, draw-relax and filament entanglement assemblies with a source of compressed air, a plurality of valves controlling the flow of air through said air lines, and means for sequentially opening said valves.
 6. The apparatus of claim 5, wherein said means for sequentially opening said valves is comprised of a plurality of plungers and means for bringing said plungers sequentially into contact with said valves.
 7. The apparatus of claim 5, wherein said means for sequentially opening said valves is comprised of a plurality of timing cams.
 8. An improved apparatus for uniformly joining two segments of multifilament yarn by air entanglement comprising a. a pneumatically operated clamping assembly comprised of a pair of spaced yarn clamps for securing the two yarn segments in abutting, parallel alignment; b. a pneumatically operated draw-relax assembly for drawing the yarn segments held between said yarn clamps to a predetermined draw ratio and then relaxing said yarn segments; c. a pneumatically operated filament entangling assembly for entangling the filaments of one yarn segment with the filaments of the other yarn segments to form a joint; and d. an actuator assembly for actuating assemblies (a), (b) and (c) in sequence whereby said draw-relax assembly is actuated after actuation of said clamping assembly and before actuation of said filament entangling assembly, said actuator Assembly comprising a plurality of air conduits connecting said clamping, draw-relax and filament entangling assemblies with a source of compressed air, a plurality of valves controlling the flow of air through said conduits, valve opening means for opening said valves in sequence and valve closing means for closing said valves.
 9. The apparatus of claim 8, wherein said apparatus is a hand-held apparatus having a pistol-shaped housing and said valve opening means comprises a trigger extending from said housing.
 10. The apparatus of claim 8, wherein said valve closing means operates independently of said valve opening means.
 11. The apparatus of claim 10, wherein said valve closing means includes a timer mechanism for closing said valves a predetermined period of time after opening of said valves by said valve opening means.
 12. The apparatus of claim 11, wherein said timer mechanism is adjustable.
 13. An improved apparatus for uniformly joining two segments of undrawn multifilament yarn by air entanglement of the filaments thereof comprising a. a yarn clamping assembly including a pair of axially aligned clamping plungers having outwardly extending yarn engaging faces, a pair of yarn guides spaced outwardly from said clamping plungers to form a pair of yarn receiving channels, and a first air chamber between said plungers, whereby introduction of compressed air into said chamber urges said plungers into said channels to clamp yarn segments between said faces and said yarn guides; b. a draw-relax assembly for drawing and relaxing yarn segments extending between said channels; c. an air entangling assembly comprised of a block having an elongated trough therein, an air nozzle communicating with said trough, a cover, and pneumatic means including a second air chamber for moving said cover into engagement with said block over said trough; and d. an actuator assembly comprised of a first air conduit connecting said first air chamber with a source of compressed air, a first valve controlling the flow of air through said first conduit, a second air conduit connecting said second air chamber with a source of compressed air, a second valve for controlling the flow of air through said second air conduit, a third air conduit connecting said air nozzle with a source of compressed air, a third valve for controlling the flow of air through said third conduit, control means for opening said first valve, then actuating said draw-relax assembly, then opening said second valve, and then opening said third valve, and timer means for maintaining at least said third valve open for a predetermined period of time.
 14. The apparatus of claim 13, wherein said draw relax assembly comprising a pair of parallel shafts carrying angularly extending yarn supporting arms having yarn engaging portions and means for rotating one of said shafts clock-wise and the other of said shafts counter-clock-wise to move said yarn engaging portions apart and then together; said trough in said block being aligned with said yarn engaging portions of said yarn supporting arms.
 15. The apparatus of claim 13, wherein said control means is a trigger and said assemblies are supported on a pistol-shaped housing.
 16. An improved apparatus for uniformly joining two segments of undrawn multifilament yarn comprising a. a pair of spaced first and second pneumatically operated yarn clamps, said second yarn clamp being moveable; b. a first pneumatic cylinder having a first plunger secured at its outer end to said second clamp, said cylinder being axially aligned with said clamps, said plunger being moveable away from said first clamp upon introduction of compressed air into said first cylinder; c. an air entangling assembly comprised of a stationary portion including a yarn receiving trough and an air nozzle communicating with said trough and a moveable cover portion; d. a second pneumatic cylinder having a second plunger secured to said moveable cover portion of said air entangling assembly and being axially aligned with said stationary and moveable portions of said air entangling assembly, said plunger being moveable toward said stationary portion upon introduction of compressed air into said cylinder; and e. actuator means for introducing compressed air in sequence to said clamps, said first cylinder, said second cylinder and said air nozzle.
 17. The apparatus of clamp 16, wherein said second plunger is positioned along an axis transverse to the axis of said first plunger and extending between said yarn clamps.
 18. The apparatus of claim 16, wherein said actuator means is comprised of air lines connecting said clamps, cylinders and air nozzle with a compressed air source, valves controlling the flow of air through said air lines, and valve opening means for sequentially opening said valves.
 19. The apparatus of claim 17, wherein said valve opening means is comprised of timing cams. 